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Posted to commits@flink.apache.org by fh...@apache.org on 2015/08/05 00:41:10 UTC

[5/5] flink git commit: [FLINK-2105] Implement Sort-Merge Outer Join algorithm

[FLINK-2105] Implement Sort-Merge Outer Join algorithm

This closes #907


Project: http://git-wip-us.apache.org/repos/asf/flink/repo
Commit: http://git-wip-us.apache.org/repos/asf/flink/commit/941ac6df
Tree: http://git-wip-us.apache.org/repos/asf/flink/tree/941ac6df
Diff: http://git-wip-us.apache.org/repos/asf/flink/diff/941ac6df

Branch: refs/heads/master
Commit: 941ac6dfd446d8e97e2fe2f589164978602adf94
Parents: df9f481
Author: r-pogalz <r....@campus.tu-berlin.de>
Authored: Mon Aug 3 12:59:48 2015 +0200
Committer: Fabian Hueske <fh...@apache.org>
Committed: Tue Aug 4 23:51:27 2015 +0200

----------------------------------------------------------------------
 .../operators/sort/AbstractMergeIterator.java   |  58 +--
 .../sort/AbstractMergeOuterJoinIterator.java    | 189 ++++++++
 .../sort/NonReusingMergeOuterJoinIterator.java  |  60 +++
 .../sort/ReusingMergeOuterJoinIterator.java     |  63 +++
 ...bstractSortMergeOuterJoinIteratorITCase.java | 462 +++++++++++++++++++
 ...ReusingSortMergeInnerJoinIteratorITCase.java |   4 +-
 ...ReusingSortMergeOuterJoinIteratorITCase.java |  82 ++++
 ...ReusingSortMergeInnerJoinIteratorITCase.java |   4 +-
 ...ReusingSortMergeOuterJoinIteratorITCase.java |  82 ++++
 .../runtime/operators/testutils/Match.java      |   2 +-
 .../testutils/MatchRemovingJoiner.java          |  58 +++
 .../testutils/MatchRemovingMatcher.java         |  58 ---
 12 files changed, 1030 insertions(+), 92 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/flink/blob/941ac6df/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/AbstractMergeIterator.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/AbstractMergeIterator.java b/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/AbstractMergeIterator.java
index 9a61c14..c01afc7 100644
--- a/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/AbstractMergeIterator.java
+++ b/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/AbstractMergeIterator.java
@@ -115,20 +115,20 @@ public abstract class AbstractMergeIterator<T1, T2, O> implements JoinTaskIterat
 	}
 
 	/**
-	 * Calls the <code>JoinFunction#match()</code> method for all two key-value pairs that share the same key and come
-	 * from different inputs. The output of the <code>match()</code> method is forwarded.
+	 * Calls the <code>JoinFunction#join()</code> method for all two key-value pairs that share the same key and come
+	 * from different inputs. The output of the <code>join()</code> method is forwarded.
 	 * <p>
 	 * This method first zig-zags between the two sorted inputs in order to find a common
-	 * key, and then calls the match stub with the cross product of the values.
+	 * key, and then calls the join stub with the cross product of the values.
 	 *
 	 * @throws Exception Forwards all exceptions from the user code and the I/O system.
 	 * @see org.apache.flink.runtime.operators.util.JoinTaskIterator#callWithNextKey(org.apache.flink.api.common.functions.FlatJoinFunction, org.apache.flink.util.Collector)
 	 */
 	@Override
-	public abstract boolean callWithNextKey(final FlatJoinFunction<T1, T2, O> matchFunction, final Collector<O> collector)
+	public abstract boolean callWithNextKey(final FlatJoinFunction<T1, T2, O> joinFunction, final Collector<O> collector)
 			throws Exception;
 
-	protected void crossMatchingGroup(Iterator<T1> values1, Iterator<T2> values2, FlatJoinFunction<T1, T2, O> matchFunction, Collector<O> collector) throws Exception {
+	protected void crossMatchingGroup(Iterator<T1> values1, Iterator<T2> values2, FlatJoinFunction<T1, T2, O> joinFunction, Collector<O> collector) throws Exception {
 		final T1 firstV1 = values1.next();
 		final T2 firstV2 = values2.next();
 
@@ -143,23 +143,23 @@ public abstract class AbstractMergeIterator<T1, T2, O> implements JoinTaskIterat
 			if (v2HasNext) {
 				// both sides contain more than one value
 				// TODO: Decide which side to spill and which to block!
-				crossMwithNValues(firstV1, values1, firstV2, values2, matchFunction, collector);
+				crossMwithNValues(firstV1, values1, firstV2, values2, joinFunction, collector);
 			} else {
-				crossSecond1withNValues(firstV2, firstV1, values1, matchFunction, collector);
+				crossSecond1withNValues(firstV2, firstV1, values1, joinFunction, collector);
 			}
 		} else {
 			if (v2HasNext) {
-				crossFirst1withNValues(firstV1, firstV2, values2, matchFunction, collector);
+				crossFirst1withNValues(firstV1, firstV2, values2, joinFunction, collector);
 			} else {
 				// both sides contain only one value
-				matchFunction.join(firstV1, firstV2, collector);
+				joinFunction.join(firstV1, firstV2, collector);
 			}
 		}
 	}
 
 	/**
 	 * Crosses a single value from the first input with N values, all sharing a common key.
-	 * Effectively realizes a <i>1:N</i> match (join).
+	 * Effectively realizes a <i>1:N</i> join.
 	 *
 	 * @param val1      The value form the <i>1</i> side.
 	 * @param firstValN The first of the values from the <i>N</i> side.
@@ -167,21 +167,21 @@ public abstract class AbstractMergeIterator<T1, T2, O> implements JoinTaskIterat
 	 * @throws Exception Forwards all exceptions thrown by the stub.
 	 */
 	private void crossFirst1withNValues(final T1 val1, final T2 firstValN,
-										final Iterator<T2> valsN, final FlatJoinFunction<T1, T2, O> matchFunction, final Collector<O> collector)
+										final Iterator<T2> valsN, final FlatJoinFunction<T1, T2, O> joinFunction, final Collector<O> collector)
 			throws Exception {
 		T1 copy1 = createCopy(serializer1, val1, this.copy1);
-		matchFunction.join(copy1, firstValN, collector);
+		joinFunction.join(copy1, firstValN, collector);
 
-		// set copy and match first element
+		// set copy and join first element
 		boolean more = true;
 		do {
 			final T2 nRec = valsN.next();
 
 			if (valsN.hasNext()) {
 				copy1 = createCopy(serializer1, val1, this.copy1);
-				matchFunction.join(copy1, nRec, collector);
+				joinFunction.join(copy1, nRec, collector);
 			} else {
-				matchFunction.join(val1, nRec, collector);
+				joinFunction.join(val1, nRec, collector);
 				more = false;
 			}
 		}
@@ -190,7 +190,7 @@ public abstract class AbstractMergeIterator<T1, T2, O> implements JoinTaskIterat
 
 	/**
 	 * Crosses a single value from the second side with N values, all sharing a common key.
-	 * Effectively realizes a <i>N:1</i> match (join).
+	 * Effectively realizes a <i>N:1</i> join.
 	 *
 	 * @param val1      The value form the <i>1</i> side.
 	 * @param firstValN The first of the values from the <i>N</i> side.
@@ -198,20 +198,20 @@ public abstract class AbstractMergeIterator<T1, T2, O> implements JoinTaskIterat
 	 * @throws Exception Forwards all exceptions thrown by the stub.
 	 */
 	private void crossSecond1withNValues(T2 val1, T1 firstValN,
-										Iterator<T1> valsN, FlatJoinFunction<T1, T2, O> matchFunction, Collector<O> collector) throws Exception {
+										Iterator<T1> valsN, FlatJoinFunction<T1, T2, O> joinFunction, Collector<O> collector) throws Exception {
 		T2 copy2 = createCopy(serializer2, val1, this.copy2);
-		matchFunction.join(firstValN, copy2, collector);
+		joinFunction.join(firstValN, copy2, collector);
 
-		// set copy and match first element
+		// set copy and join first element
 		boolean more = true;
 		do {
 			final T1 nRec = valsN.next();
 
 			if (valsN.hasNext()) {
 				copy2 = createCopy(serializer2, val1, this.copy2);
-				matchFunction.join(nRec, copy2, collector);
+				joinFunction.join(nRec, copy2, collector);
 			} else {
-				matchFunction.join(nRec, val1, collector);
+				joinFunction.join(nRec, val1, collector);
 				more = false;
 			}
 		}
@@ -220,7 +220,7 @@ public abstract class AbstractMergeIterator<T1, T2, O> implements JoinTaskIterat
 
 	private void crossMwithNValues(final T1 firstV1, Iterator<T1> spillVals,
 									final T2 firstV2, final Iterator<T2> blockVals,
-									final FlatJoinFunction<T1, T2, O> matchFunction, final Collector<O> collector) throws Exception {
+									final FlatJoinFunction<T1, T2, O> joinFunction, final Collector<O> collector) throws Exception {
 		// ==================================================
 		// We have one first (head) element from both inputs (firstV1 and firstV2)
 		// We have an iterator for both inputs.
@@ -237,13 +237,13 @@ public abstract class AbstractMergeIterator<T1, T2, O> implements JoinTaskIterat
 		// 5) cross the head of the spilling side with the next block
 		// 6) cross the spilling iterator with the next block.
 
-		// match the first values first
+		// join the first values first
 		T1 copy1 = this.createCopy(serializer1, firstV1, this.copy1);
 		T2 blockHeadCopy = this.createCopy(serializer2, firstV2, this.blockHeadCopy);
 		T1 spillHeadCopy = null;
 
 		// --------------- 1) Cross the heads -------------------
-		matchFunction.join(copy1, firstV2, collector);
+		joinFunction.join(copy1, firstV2, collector);
 
 		// for the remaining values, we do a block-nested-loops join
 		SpillingResettableIterator<T1> spillIt = null;
@@ -256,7 +256,7 @@ public abstract class AbstractMergeIterator<T1, T2, O> implements JoinTaskIterat
 			while (this.blockIt.hasNext()) {
 				final T2 nextBlockRec = this.blockIt.next();
 				copy1 = this.createCopy(serializer1, firstV1, this.copy1);
-				matchFunction.join(copy1, nextBlockRec, collector);
+				joinFunction.join(copy1, nextBlockRec, collector);
 			}
 			this.blockIt.reset();
 
@@ -286,7 +286,7 @@ public abstract class AbstractMergeIterator<T1, T2, O> implements JoinTaskIterat
 
 				// -------- 3) cross the iterator of the spilling side with the head of the block side --------
 				T2 copy2 = this.createCopy(serializer2, blockHeadCopy, this.copy2);
-				matchFunction.join(copy1, copy2, collector);
+				joinFunction.join(copy1, copy2, collector);
 
 				// -------- 4) cross the iterator of the spilling side with the first block --------
 				while (this.blockIt.hasNext()) {
@@ -294,7 +294,7 @@ public abstract class AbstractMergeIterator<T1, T2, O> implements JoinTaskIterat
 
 					// get instances of key and block value
 					copy1 = this.createCopy(serializer1, nextSpillVal, this.copy1);
-					matchFunction.join(copy1, nextBlockRec, collector);
+					joinFunction.join(copy1, nextBlockRec, collector);
 				}
 				// reset block iterator
 				this.blockIt.reset();
@@ -316,7 +316,7 @@ public abstract class AbstractMergeIterator<T1, T2, O> implements JoinTaskIterat
 				while (this.blockIt.hasNext()) {
 					copy1 = this.createCopy(serializer1, spillHeadCopy, this.copy1);
 					final T2 nextBlockVal = blockIt.next();
-					matchFunction.join(copy1, nextBlockVal, collector);
+					joinFunction.join(copy1, nextBlockVal, collector);
 				}
 				this.blockIt.reset();
 
@@ -329,7 +329,7 @@ public abstract class AbstractMergeIterator<T1, T2, O> implements JoinTaskIterat
 						// get instances of key and block value
 						final T2 nextBlockVal = this.blockIt.next();
 						copy1 = this.createCopy(serializer1, nextSpillVal, this.copy1);
-						matchFunction.join(copy1, nextBlockVal, collector);
+						joinFunction.join(copy1, nextBlockVal, collector);
 					}
 
 					// reset block iterator

http://git-wip-us.apache.org/repos/asf/flink/blob/941ac6df/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/AbstractMergeOuterJoinIterator.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/AbstractMergeOuterJoinIterator.java b/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/AbstractMergeOuterJoinIterator.java
new file mode 100644
index 0000000..01b371e
--- /dev/null
+++ b/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/AbstractMergeOuterJoinIterator.java
@@ -0,0 +1,189 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.flink.runtime.operators.sort;
+
+import org.apache.flink.api.common.functions.FlatJoinFunction;
+import org.apache.flink.api.common.typeutils.TypeComparator;
+import org.apache.flink.api.common.typeutils.TypePairComparator;
+import org.apache.flink.api.common.typeutils.TypeSerializer;
+import org.apache.flink.runtime.io.disk.iomanager.IOManager;
+import org.apache.flink.runtime.jobgraph.tasks.AbstractInvokable;
+import org.apache.flink.runtime.memorymanager.MemoryAllocationException;
+import org.apache.flink.runtime.memorymanager.MemoryManager;
+import org.apache.flink.util.Collector;
+import org.apache.flink.util.MutableObjectIterator;
+
+import java.util.Iterator;
+
+/**
+ * An implementation of the {@link org.apache.flink.runtime.operators.util.JoinTaskIterator} that realizes the
+ * outer join through a sort-merge join strategy.
+ */
+public abstract class AbstractMergeOuterJoinIterator<T1, T2, O> extends AbstractMergeIterator<T1, T2, O> {
+
+	public static enum OuterJoinType {LEFT, RIGHT, FULL}
+
+	private final OuterJoinType outerJoinType;
+
+	private boolean initialized = false;
+	private boolean it1Empty = false;
+	private boolean it2Empty = false;
+
+
+	public AbstractMergeOuterJoinIterator(
+			OuterJoinType outerJoinType,
+			MutableObjectIterator<T1> input1,
+			MutableObjectIterator<T2> input2,
+			TypeSerializer<T1> serializer1, TypeComparator<T1> comparator1,
+			TypeSerializer<T2> serializer2, TypeComparator<T2> comparator2,
+			TypePairComparator<T1, T2> pairComparator,
+			MemoryManager memoryManager,
+			IOManager ioManager,
+			int numMemoryPages,
+			AbstractInvokable parentTask)
+			throws MemoryAllocationException {
+		super(input1, input2, serializer1, comparator1, serializer2, comparator2, pairComparator, memoryManager, ioManager, numMemoryPages, parentTask);
+
+		this.outerJoinType = outerJoinType;
+	}
+
+	/**
+	 * Calls the <code>JoinFunction#join()</code> method for all two key-value pairs that share the same key and come
+	 * from different inputs. Furthermore, depending on the outer join type (LEFT, RIGHT, FULL), all key-value pairs where no
+	 * matching partner from the other input exists are joined with null.
+	 * The output of the <code>join()</code> method is forwarded.
+	 *
+	 * @throws Exception Forwards all exceptions from the user code and the I/O system.
+	 * @see org.apache.flink.runtime.operators.util.JoinTaskIterator#callWithNextKey(org.apache.flink.api.common.functions.FlatJoinFunction, org.apache.flink.util.Collector)
+	 */
+	@Override
+	public boolean callWithNextKey(final FlatJoinFunction<T1, T2, O> joinFunction, final Collector<O> collector) throws Exception {
+		if (!initialized) {
+			//first run, set iterators to first elements
+			it1Empty = !this.iterator1.nextKey();
+			it2Empty = !this.iterator2.nextKey();
+			initialized = true;
+		}
+
+		if (it1Empty && it2Empty) {
+			return false;
+		} else if (it2Empty) {
+			if (outerJoinType == OuterJoinType.LEFT || outerJoinType == OuterJoinType.FULL) {
+				joinLeftKeyValuesWithNull(iterator1.getValues(), joinFunction, collector);
+				it1Empty = !iterator1.nextKey();
+				return true;
+			} else {
+				//consume rest of left side
+				while (iterator1.nextKey()) ;
+				it1Empty = true;
+				return false;
+			}
+		} else if (it1Empty) {
+			if (outerJoinType == OuterJoinType.RIGHT || outerJoinType == OuterJoinType.FULL) {
+				joinRightKeyValuesWithNull(iterator2.getValues(), joinFunction, collector);
+				it2Empty = !iterator2.nextKey();
+				return true;
+			} else {
+				//consume rest of right side
+				while (iterator2.nextKey()) ;
+				it2Empty = true;
+				return false;
+			}
+		} else {
+			final TypePairComparator<T1, T2> comparator = super.pairComparator;
+			comparator.setReference(this.iterator1.getCurrent());
+			T2 current2 = this.iterator2.getCurrent();
+
+			// zig zag
+			while (true) {
+				// determine the relation between the (possibly composite) keys
+				final int comp = comparator.compareToReference(current2);
+
+				if (comp == 0) {
+					break;
+				}
+
+				if (comp < 0) {
+					//right key < left key
+					if (outerJoinType == OuterJoinType.RIGHT || outerJoinType == OuterJoinType.FULL) {
+						//join right key values with null in case of right or full outer join
+						joinRightKeyValuesWithNull(iterator2.getValues(), joinFunction, collector);
+						it2Empty = !iterator2.nextKey();
+						return true;
+					} else {
+						//skip this right key if it is a left outer join
+						if (!this.iterator2.nextKey()) {
+							//if right side is empty, join current left key values with null
+							joinLeftKeyValuesWithNull(iterator1.getValues(), joinFunction, collector);
+							it1Empty = !iterator1.nextKey();
+							it2Empty = true;
+							return true;
+						}
+						current2 = this.iterator2.getCurrent();
+					}
+				} else {
+					//right key > left key
+					if (outerJoinType == OuterJoinType.LEFT || outerJoinType == OuterJoinType.FULL) {
+						//join left key values with null in case of left or full outer join
+						joinLeftKeyValuesWithNull(iterator1.getValues(), joinFunction, collector);
+						it1Empty = !iterator1.nextKey();
+						return true;
+					} else {
+						//skip this left key if it is a right outer join
+						if (!this.iterator1.nextKey()) {
+							//if right side is empty, join current right key values with null
+							joinRightKeyValuesWithNull(iterator2.getValues(), joinFunction, collector);
+							it1Empty = true;
+							it2Empty = !iterator2.nextKey();
+							return true;
+						}
+						comparator.setReference(this.iterator1.getCurrent());
+					}
+				}
+			}
+
+			// here, we have a common key! call the join function with the cross product of the
+			// values
+			final Iterator<T1> values1 = this.iterator1.getValues();
+			final Iterator<T2> values2 = this.iterator2.getValues();
+
+			crossMatchingGroup(values1, values2, joinFunction, collector);
+			it1Empty = !iterator1.nextKey();
+			it2Empty = !iterator2.nextKey();
+			return true;
+		}
+	}
+
+	private void joinLeftKeyValuesWithNull(Iterator<T1> values, FlatJoinFunction<T1, T2, O> joinFunction, Collector<O> collector) throws Exception {
+		while (values.hasNext()) {
+			T1 next = values.next();
+			this.copy1 = createCopy(serializer1, next, copy1);
+			joinFunction.join(copy1, null, collector);
+		}
+	}
+
+	private void joinRightKeyValuesWithNull(Iterator<T2> values, FlatJoinFunction<T1, T2, O> joinFunction, Collector<O> collector) throws Exception {
+		while (values.hasNext()) {
+			T2 next = values.next();
+			this.copy2 = createCopy(serializer2, next, copy2);
+			joinFunction.join(null, copy2, collector);
+		}
+	}
+
+}

http://git-wip-us.apache.org/repos/asf/flink/blob/941ac6df/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/NonReusingMergeOuterJoinIterator.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/NonReusingMergeOuterJoinIterator.java b/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/NonReusingMergeOuterJoinIterator.java
new file mode 100644
index 0000000..ac49ece
--- /dev/null
+++ b/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/NonReusingMergeOuterJoinIterator.java
@@ -0,0 +1,60 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.flink.runtime.operators.sort;
+
+import org.apache.flink.api.common.typeutils.TypeComparator;
+import org.apache.flink.api.common.typeutils.TypePairComparator;
+import org.apache.flink.api.common.typeutils.TypeSerializer;
+import org.apache.flink.runtime.io.disk.iomanager.IOManager;
+import org.apache.flink.runtime.jobgraph.tasks.AbstractInvokable;
+import org.apache.flink.runtime.memorymanager.MemoryAllocationException;
+import org.apache.flink.runtime.memorymanager.MemoryManager;
+import org.apache.flink.runtime.util.KeyGroupedIterator;
+import org.apache.flink.runtime.util.NonReusingKeyGroupedIterator;
+import org.apache.flink.util.MutableObjectIterator;
+
+public class NonReusingMergeOuterJoinIterator<T1, T2, O> extends AbstractMergeOuterJoinIterator<T1, T2, O> {
+
+	public NonReusingMergeOuterJoinIterator(
+			OuterJoinType outerJoinType,
+			MutableObjectIterator<T1> input1,
+			MutableObjectIterator<T2> input2,
+			TypeSerializer<T1> serializer1, TypeComparator<T1> comparator1,
+			TypeSerializer<T2> serializer2, TypeComparator<T2> comparator2,
+			TypePairComparator<T1, T2> pairComparator,
+			MemoryManager memoryManager,
+			IOManager ioManager,
+			int numMemoryPages,
+			AbstractInvokable parentTask)
+			throws MemoryAllocationException {
+		super(outerJoinType, input1, input2, serializer1, comparator1, serializer2, comparator2, pairComparator, memoryManager, ioManager, numMemoryPages, parentTask);
+	}
+
+	@Override
+	protected <T> KeyGroupedIterator<T> createKeyGroupedIterator(MutableObjectIterator<T> input, TypeSerializer<T> serializer, TypeComparator<T> comparator) {
+		return new NonReusingKeyGroupedIterator<T>(input, comparator);
+	}
+
+	@Override
+	protected <T> T createCopy(TypeSerializer<T> serializer, T value, T reuse) {
+		return serializer.copy(value);
+	}
+
+
+}

http://git-wip-us.apache.org/repos/asf/flink/blob/941ac6df/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/ReusingMergeOuterJoinIterator.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/ReusingMergeOuterJoinIterator.java b/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/ReusingMergeOuterJoinIterator.java
new file mode 100644
index 0000000..0cefbc5
--- /dev/null
+++ b/flink-runtime/src/main/java/org/apache/flink/runtime/operators/sort/ReusingMergeOuterJoinIterator.java
@@ -0,0 +1,63 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.flink.runtime.operators.sort;
+
+import org.apache.flink.api.common.typeutils.TypeComparator;
+import org.apache.flink.api.common.typeutils.TypePairComparator;
+import org.apache.flink.api.common.typeutils.TypeSerializer;
+import org.apache.flink.runtime.io.disk.iomanager.IOManager;
+import org.apache.flink.runtime.jobgraph.tasks.AbstractInvokable;
+import org.apache.flink.runtime.memorymanager.MemoryAllocationException;
+import org.apache.flink.runtime.memorymanager.MemoryManager;
+import org.apache.flink.runtime.util.KeyGroupedIterator;
+import org.apache.flink.runtime.util.ReusingKeyGroupedIterator;
+import org.apache.flink.util.MutableObjectIterator;
+
+public class ReusingMergeOuterJoinIterator<T1, T2, O> extends AbstractMergeOuterJoinIterator<T1, T2, O> {
+
+	public ReusingMergeOuterJoinIterator(
+			OuterJoinType outerJoinType,
+			MutableObjectIterator<T1> input1,
+			MutableObjectIterator<T2> input2,
+			TypeSerializer<T1> serializer1, TypeComparator<T1> comparator1,
+			TypeSerializer<T2> serializer2, TypeComparator<T2> comparator2,
+			TypePairComparator<T1, T2> pairComparator,
+			MemoryManager memoryManager,
+			IOManager ioManager,
+			int numMemoryPages,
+			AbstractInvokable parentTask)
+			throws MemoryAllocationException {
+		super(outerJoinType, input1, input2, serializer1, comparator1, serializer2, comparator2, pairComparator, memoryManager, ioManager, numMemoryPages, parentTask);
+
+		this.copy1 = serializer1.createInstance();
+		this.spillHeadCopy = serializer1.createInstance();
+		this.copy2 = serializer2.createInstance();
+		this.blockHeadCopy = serializer2.createInstance();
+	}
+
+	@Override
+	protected <T> KeyGroupedIterator<T> createKeyGroupedIterator(MutableObjectIterator<T> input, TypeSerializer<T> serializer, TypeComparator<T> comparator) {
+		return new ReusingKeyGroupedIterator<T>(input, serializer, comparator);
+	}
+
+	@Override
+	protected <T> T createCopy(TypeSerializer<T> serializer, T value, T reuse) { return serializer.copy(value, reuse); }
+
+
+}
\ No newline at end of file

http://git-wip-us.apache.org/repos/asf/flink/blob/941ac6df/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/AbstractSortMergeOuterJoinIteratorITCase.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/AbstractSortMergeOuterJoinIteratorITCase.java b/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/AbstractSortMergeOuterJoinIteratorITCase.java
new file mode 100644
index 0000000..1fbe025
--- /dev/null
+++ b/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/AbstractSortMergeOuterJoinIteratorITCase.java
@@ -0,0 +1,462 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.flink.runtime.operators.sort;
+
+import org.apache.flink.api.common.ExecutionConfig;
+import org.apache.flink.api.common.functions.FlatJoinFunction;
+import org.apache.flink.api.common.functions.util.ListCollector;
+import org.apache.flink.api.common.typeutils.GenericPairComparator;
+import org.apache.flink.api.common.typeutils.TypeComparator;
+import org.apache.flink.api.common.typeutils.TypePairComparator;
+import org.apache.flink.api.common.typeutils.TypeSerializer;
+import org.apache.flink.api.common.typeutils.base.IntComparator;
+import org.apache.flink.api.common.typeutils.base.IntSerializer;
+import org.apache.flink.api.common.typeutils.base.StringSerializer;
+import org.apache.flink.api.java.tuple.Tuple2;
+import org.apache.flink.api.java.tuple.Tuple4;
+import org.apache.flink.api.java.typeutils.TupleTypeInfo;
+import org.apache.flink.api.java.typeutils.runtime.TupleComparator;
+import org.apache.flink.api.java.typeutils.runtime.TupleSerializer;
+import org.apache.flink.runtime.io.disk.iomanager.IOManager;
+import org.apache.flink.runtime.io.disk.iomanager.IOManagerAsync;
+import org.apache.flink.runtime.jobgraph.tasks.AbstractInvokable;
+import org.apache.flink.runtime.memorymanager.DefaultMemoryManager;
+import org.apache.flink.runtime.memorymanager.MemoryManager;
+import org.apache.flink.runtime.operators.sort.AbstractMergeOuterJoinIterator.OuterJoinType;
+import org.apache.flink.runtime.operators.testutils.*;
+import org.apache.flink.runtime.operators.testutils.TestData.TupleConstantValueIterator;
+import org.apache.flink.runtime.operators.testutils.TestData.TupleGenerator;
+import org.apache.flink.runtime.operators.testutils.TestData.TupleGenerator.KeyMode;
+import org.apache.flink.runtime.operators.testutils.TestData.TupleGenerator.ValueMode;
+import org.apache.flink.runtime.operators.testutils.TestData.TupleGeneratorIterator;
+import org.apache.flink.runtime.util.ResettableMutableObjectIterator;
+import org.apache.flink.util.Collector;
+import org.apache.flink.util.MutableObjectIterator;
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Before;
+
+import java.util.*;
+import java.util.Map.Entry;
+
+public abstract class AbstractSortMergeOuterJoinIteratorITCase {
+
+	// total memory
+	private static final int MEMORY_SIZE = 1024 * 1024 * 16;
+	private static final int PAGES_FOR_BNLJN = 2;
+
+	// the size of the left and right inputs
+	private static final int INPUT_1_SIZE = 20000;
+
+	private static final int INPUT_2_SIZE = 1000;
+
+	// random seeds for the left and right input data generators
+	private static final long SEED1 = 561349061987311L;
+
+	private static final long SEED2 = 231434613412342L;
+
+	// dummy abstract task
+	private final AbstractInvokable parentTask = new DummyInvokable();
+
+	private IOManager ioManager;
+	private MemoryManager memoryManager;
+
+	private TupleTypeInfo<Tuple2<String, String>> typeInfo1;
+	private TupleTypeInfo<Tuple2<String, Integer>> typeInfo2;
+	private TupleSerializer<Tuple2<String, String>> serializer1;
+	private TupleSerializer<Tuple2<String, Integer>> serializer2;
+	private TypeComparator<Tuple2<String, String>> comparator1;
+	private TypeComparator<Tuple2<String, Integer>> comparator2;
+	private TypePairComparator<Tuple2<String, String>, Tuple2<String, Integer>> pairComp;
+
+
+	@Before
+	public void beforeTest() {
+		ExecutionConfig config = new ExecutionConfig();
+		config.disableObjectReuse();
+
+		typeInfo1 = TupleTypeInfo.getBasicTupleTypeInfo(String.class, String.class);
+		typeInfo2 = TupleTypeInfo.getBasicTupleTypeInfo(String.class, Integer.class);
+		serializer1 = typeInfo1.createSerializer(config);
+		serializer2 = typeInfo2.createSerializer(config);
+		comparator1 = typeInfo1.createComparator(new int[]{0}, new boolean[]{true}, 0, config);
+		comparator2 = typeInfo2.createComparator(new int[]{0}, new boolean[]{true}, 0, config);
+		pairComp = new GenericPairComparator<Tuple2<String, String>, Tuple2<String, Integer>>(comparator1, comparator2);
+
+		this.memoryManager = new DefaultMemoryManager(MEMORY_SIZE, 1);
+		this.ioManager = new IOManagerAsync();
+	}
+
+	@After
+	public void afterTest() {
+		if (this.ioManager != null) {
+			this.ioManager.shutdown();
+			if (!this.ioManager.isProperlyShutDown()) {
+				Assert.fail("I/O manager failed to properly shut down.");
+			}
+			this.ioManager = null;
+		}
+
+		if (this.memoryManager != null) {
+			Assert.assertTrue("Memory Leak: Not all memory has been returned to the memory manager.",
+					this.memoryManager.verifyEmpty());
+			this.memoryManager.shutdown();
+			this.memoryManager = null;
+		}
+	}
+
+	protected void testFullOuterWithSample() throws Exception {
+		CollectionIterator<Tuple2<String, String>> input1 = CollectionIterator.of(
+				new Tuple2<String, String>("Jack", "Engineering"),
+				new Tuple2<String, String>("Tim", "Sales"),
+				new Tuple2<String, String>("Zed", "HR")
+		);
+		CollectionIterator<Tuple2<String, Integer>> input2 = CollectionIterator.of(
+				new Tuple2<String, Integer>("Allison", 100),
+				new Tuple2<String, Integer>("Jack", 200),
+				new Tuple2<String, Integer>("Zed", 150),
+				new Tuple2<String, Integer>("Zed", 250)
+		);
+
+		OuterJoinType outerJoinType = OuterJoinType.FULL;
+		List<Tuple4<String, String, String, Object>> actual = computeOuterJoin(input1, input2, outerJoinType);
+
+		List<Tuple4<String, String, String, Object>> expected = Arrays.asList(
+				new Tuple4<String, String, String, Object>(null, null, "Allison", 100),
+				new Tuple4<String, String, String, Object>("Jack", "Engineering", "Jack", 200),
+				new Tuple4<String, String, String, Object>("Tim", "Sales", null, null),
+				new Tuple4<String, String, String, Object>("Zed", "HR", "Zed", 150),
+				new Tuple4<String, String, String, Object>("Zed", "HR", "Zed", 250)
+		);
+
+		Assert.assertEquals(expected, actual);
+	}
+
+	protected void testLeftOuterWithSample() throws Exception {
+		CollectionIterator<Tuple2<String, String>> input1 = CollectionIterator.of(
+				new Tuple2<String, String>("Jack", "Engineering"),
+				new Tuple2<String, String>("Tim", "Sales"),
+				new Tuple2<String, String>("Zed", "HR")
+		);
+		CollectionIterator<Tuple2<String, Integer>> input2 = CollectionIterator.of(
+				new Tuple2<String, Integer>("Allison", 100),
+				new Tuple2<String, Integer>("Jack", 200),
+				new Tuple2<String, Integer>("Zed", 150),
+				new Tuple2<String, Integer>("Zed", 250)
+		);
+
+		List<Tuple4<String, String, String, Object>> actual = computeOuterJoin(input1, input2, OuterJoinType.LEFT);
+
+		List<Tuple4<String, String, String, Object>> expected = Arrays.asList(
+				new Tuple4<String, String, String, Object>("Jack", "Engineering", "Jack", 200),
+				new Tuple4<String, String, String, Object>("Tim", "Sales", null, null),
+				new Tuple4<String, String, String, Object>("Zed", "HR", "Zed", 150),
+				new Tuple4<String, String, String, Object>("Zed", "HR", "Zed", 250)
+		);
+
+		Assert.assertEquals(expected, actual);
+	}
+
+	protected void testRightOuterWithSample() throws Exception {
+		CollectionIterator<Tuple2<String, String>> input1 = CollectionIterator.of(
+				new Tuple2<String, String>("Jack", "Engineering"),
+				new Tuple2<String, String>("Tim", "Sales"),
+				new Tuple2<String, String>("Zed", "HR")
+		);
+		CollectionIterator<Tuple2<String, Integer>> input2 = CollectionIterator.of(
+				new Tuple2<String, Integer>("Allison", 100),
+				new Tuple2<String, Integer>("Jack", 200),
+				new Tuple2<String, Integer>("Zed", 150),
+				new Tuple2<String, Integer>("Zed", 250)
+		);
+
+		List<Tuple4<String, String, String, Object>> actual = computeOuterJoin(input1, input2, OuterJoinType.RIGHT);
+
+		List<Tuple4<String, String, String, Object>> expected = Arrays.asList(
+				new Tuple4<String, String, String, Object>(null, null, "Allison", 100),
+				new Tuple4<String, String, String, Object>("Jack", "Engineering", "Jack", 200),
+				new Tuple4<String, String, String, Object>("Zed", "HR", "Zed", 150),
+				new Tuple4<String, String, String, Object>("Zed", "HR", "Zed", 250)
+		);
+
+		Assert.assertEquals(expected, actual);
+	}
+
+	protected void testRightSideEmpty() throws Exception {
+		CollectionIterator<Tuple2<String, String>> input1 = CollectionIterator.of(
+				new Tuple2<String, String>("Jack", "Engineering"),
+				new Tuple2<String, String>("Tim", "Sales"),
+				new Tuple2<String, String>("Zed", "HR")
+		);
+		CollectionIterator<Tuple2<String, Integer>> input2 = CollectionIterator.of();
+
+		List<Tuple4<String, String, String, Object>> actualLeft = computeOuterJoin(input1, input2, OuterJoinType.LEFT);
+		List<Tuple4<String, String, String, Object>> actualRight = computeOuterJoin(input1, input2, OuterJoinType.RIGHT);
+		List<Tuple4<String, String, String, Object>> actualFull = computeOuterJoin(input1, input2, OuterJoinType.FULL);
+
+		List<Tuple4<String, String, String, Object>> expected = Arrays.asList(
+				new Tuple4<String, String, String, Object>("Jack", "Engineering", null, null),
+				new Tuple4<String, String, String, Object>("Tim", "Sales", null, null),
+				new Tuple4<String, String, String, Object>("Zed", "HR", null, null)
+		);
+
+		Assert.assertEquals(expected, actualLeft);
+		Assert.assertEquals(expected, actualFull);
+		Assert.assertEquals(Collections.<Tuple4<String,String,String,Object>>emptyList(), actualRight);
+	}
+
+	protected void testLeftSideEmpty() throws Exception {
+		CollectionIterator<Tuple2<String, String>> input1 = CollectionIterator.of();
+		CollectionIterator<Tuple2<String, Integer>> input2 = CollectionIterator.of(
+				new Tuple2<String, Integer>("Allison", 100),
+				new Tuple2<String, Integer>("Jack", 200),
+				new Tuple2<String, Integer>("Zed", 150),
+				new Tuple2<String, Integer>("Zed", 250)
+		);
+
+		List<Tuple4<String, String, String, Object>> actualLeft = computeOuterJoin(input1, input2, OuterJoinType.LEFT);
+		List<Tuple4<String, String, String, Object>> actualRight = computeOuterJoin(input1, input2, OuterJoinType.RIGHT);
+		List<Tuple4<String, String, String, Object>> actualFull = computeOuterJoin(input1, input2, OuterJoinType.FULL);
+
+		List<Tuple4<String, String, String, Object>> expected = Arrays.asList(
+				new Tuple4<String, String, String, Object>(null, null, "Allison", 100),
+				new Tuple4<String, String, String, Object>(null, null, "Jack", 200),
+				new Tuple4<String, String, String, Object>(null, null, "Zed", 150),
+				new Tuple4<String, String, String, Object>(null, null, "Zed", 250)
+		);
+
+		Assert.assertEquals(Collections.<Tuple4<String,String,String,Object>>emptyList(), actualLeft);
+		Assert.assertEquals(expected, actualRight);
+		Assert.assertEquals(expected, actualFull);
+	}
+
+	private List<Tuple4<String, String, String, Object>> computeOuterJoin(ResettableMutableObjectIterator<Tuple2<String, String>> input1,
+																		  ResettableMutableObjectIterator<Tuple2<String, Integer>> input2,
+																		  OuterJoinType outerJoinType) throws Exception {
+		input1.reset();
+		input2.reset();
+		AbstractMergeOuterJoinIterator<Tuple2<String, String>, Tuple2<String, Integer>, Tuple4<String, String, String, Object>> iterator =
+				createOuterJoinIterator(outerJoinType, input1, input2, serializer1, comparator1, serializer2, comparator2,
+						pairComp, this.memoryManager, this.ioManager, PAGES_FOR_BNLJN, this.parentTask);
+
+		List<Tuple4<String, String, String, Object>> actual = new ArrayList<Tuple4<String, String, String, Object>>();
+		ListCollector<Tuple4<String, String, String, Object>> collector = new ListCollector<Tuple4<String, String, String, Object>>(actual);
+		while (iterator.callWithNextKey(new SimpleTupleJoinFunction(), collector)) ;
+		iterator.close();
+
+		return actual;
+	}
+
+	protected void testOuterJoinWithHighNumberOfCommonKeys(OuterJoinType outerJoinType, int input1Size, int input1Duplicates, int input1ValueLength,
+														float input1KeyDensity, int input2Size, int input2Duplicates, int input2ValueLength, float input2KeyDensity) {
+		TypeSerializer<Tuple2<Integer, String>> serializer1 = new TupleSerializer<Tuple2<Integer, String>>(
+				(Class<Tuple2<Integer, String>>) (Class<?>) Tuple2.class,
+				new TypeSerializer<?>[] { IntSerializer.INSTANCE, StringSerializer.INSTANCE });
+		TypeSerializer<Tuple2<Integer, String>> serializer2 = new TupleSerializer<Tuple2<Integer, String>>(
+				(Class<Tuple2<Integer, String>>) (Class<?>) Tuple2.class,
+				new TypeSerializer<?>[] { IntSerializer.INSTANCE, StringSerializer.INSTANCE });
+		TypeComparator<Tuple2<Integer, String>> comparator1 =  new TupleComparator<Tuple2<Integer, String>>(
+				new int[]{0},
+				new TypeComparator<?>[] { new IntComparator(true) },
+				new TypeSerializer<?>[] { IntSerializer.INSTANCE });
+		TypeComparator<Tuple2<Integer, String>> comparator2 =  new TupleComparator<Tuple2<Integer, String>>(
+				new int[]{0},
+				new TypeComparator<?>[] { new IntComparator(true) },
+				new TypeSerializer<?>[] { IntSerializer.INSTANCE });
+
+		TypePairComparator<Tuple2<Integer, String>, Tuple2<Integer, String>> pairComparator =
+				new GenericPairComparator<Tuple2<Integer, String>, Tuple2<Integer, String>>(comparator1, comparator2);
+
+		this.memoryManager = new DefaultMemoryManager(MEMORY_SIZE, 1);
+		this.ioManager = new IOManagerAsync();
+
+		final int DUPLICATE_KEY = 13;
+
+		try {
+			final TupleGenerator generator1 = new TupleGenerator(SEED1, 500, input1KeyDensity, input1ValueLength, KeyMode.SORTED_SPARSE, ValueMode.RANDOM_LENGTH, null);
+			final TupleGenerator generator2 = new TupleGenerator(SEED2, 500, input2KeyDensity, input2ValueLength, KeyMode.SORTED_SPARSE, ValueMode.RANDOM_LENGTH, null);
+
+			final TupleGeneratorIterator gen1Iter = new TupleGeneratorIterator(generator1, input1Size);
+			final TupleGeneratorIterator gen2Iter = new TupleGeneratorIterator(generator2, input2Size);
+
+			final TupleConstantValueIterator const1Iter = new TupleConstantValueIterator(DUPLICATE_KEY, "LEFT String for Duplicate Keys", input1Duplicates);
+			final TupleConstantValueIterator const2Iter = new TupleConstantValueIterator(DUPLICATE_KEY, "RIGHT String for Duplicate Keys", input2Duplicates);
+
+			final List<MutableObjectIterator<Tuple2<Integer, String>>> inList1 = new ArrayList<MutableObjectIterator<Tuple2<Integer, String>>>();
+			inList1.add(gen1Iter);
+			inList1.add(const1Iter);
+
+			final List<MutableObjectIterator<Tuple2<Integer, String>>> inList2 = new ArrayList<MutableObjectIterator<Tuple2<Integer, String>>>();
+			inList2.add(gen2Iter);
+			inList2.add(const2Iter);
+
+			MutableObjectIterator<Tuple2<Integer, String>> input1 = new MergeIterator<Tuple2<Integer, String>>(inList1, comparator1.duplicate());
+			MutableObjectIterator<Tuple2<Integer, String>> input2 = new MergeIterator<Tuple2<Integer, String>>(inList2, comparator2.duplicate());
+
+			// collect expected data
+			final Map<Integer, Collection<Match>> expectedMatchesMap = joinValues(
+					collectData(input1),
+					collectData(input2),
+					outerJoinType);
+
+			// re-create the whole thing for actual processing
+
+			// reset the generators and iterators
+			generator1.reset();
+			generator2.reset();
+			const1Iter.reset();
+			const2Iter.reset();
+			gen1Iter.reset();
+			gen2Iter.reset();
+
+			inList1.clear();
+			inList1.add(gen1Iter);
+			inList1.add(const1Iter);
+
+			inList2.clear();
+			inList2.add(gen2Iter);
+			inList2.add(const2Iter);
+
+			input1 = new MergeIterator<Tuple2<Integer, String>>(inList1, comparator1.duplicate());
+			input2 = new MergeIterator<Tuple2<Integer, String>>(inList2, comparator2.duplicate());
+
+			final FlatJoinFunction<Tuple2<Integer, String>, Tuple2<Integer, String>, Tuple2<Integer, String>> joinFunction =
+					new MatchRemovingJoiner(expectedMatchesMap);
+
+			final Collector<Tuple2<Integer, String>> collector = new DiscardingOutputCollector<Tuple2<Integer, String>>();
+
+
+			// we create this sort-merge iterator with little memory for the block-nested-loops fall-back to make sure it
+			// needs to spill for the duplicate keys
+			AbstractMergeOuterJoinIterator<Tuple2<Integer, String>, Tuple2<Integer, String>, Tuple2<Integer, String>> iterator =
+					createOuterJoinIterator(
+							outerJoinType, input1, input2, serializer1, comparator1, serializer2, comparator2,
+							pairComparator, this.memoryManager, this.ioManager, PAGES_FOR_BNLJN, this.parentTask);
+
+			iterator.open();
+
+			while (iterator.callWithNextKey(joinFunction, collector)) ;
+
+			iterator.close();
+
+			// assert that each expected match was seen
+			for (Entry<Integer, Collection<Match>> entry : expectedMatchesMap.entrySet()) {
+				if (!entry.getValue().isEmpty()) {
+					Assert.fail("Collection for key " + entry.getKey() + " is not empty");
+				}
+			}
+		} catch (Exception e) {
+			e.printStackTrace();
+			Assert.fail("An exception occurred during the test: " + e.getMessage());
+		}
+	}
+
+	protected abstract <T1, T2> AbstractMergeOuterJoinIterator createOuterJoinIterator(OuterJoinType outerJoinType,
+																			  MutableObjectIterator<T1> input1,
+																			  MutableObjectIterator<T2> input2,
+																			  TypeSerializer<T1> serializer1, TypeComparator<T1> comparator1,
+																			  TypeSerializer<T2> serializer2, TypeComparator<T2> comparator2,
+																			  TypePairComparator<T1, T2> pairComparator,
+																			  MemoryManager memoryManager,
+																			  IOManager ioManager,
+																			  int numMemoryPages,
+																			  AbstractInvokable parentTask) throws Exception;
+
+	// --------------------------------------------------------------------------------------------
+	//                                    Utilities
+	// --------------------------------------------------------------------------------------------
+
+
+	private Map<Integer, Collection<Match>> joinValues(
+			Map<Integer, Collection<String>> leftMap,
+			Map<Integer, Collection<String>> rightMap,
+			OuterJoinType outerJoinType) {
+		Map<Integer, Collection<Match>> map = new HashMap<Integer, Collection<Match>>();
+
+		for (Integer key : leftMap.keySet()) {
+			Collection<String> leftValues = leftMap.get(key);
+			Collection<String> rightValues = rightMap.get(key);
+
+			if (outerJoinType == OuterJoinType.RIGHT && rightValues == null) {
+				continue;
+			}
+
+			if (!map.containsKey(key)) {
+				map.put(key, new ArrayList<Match>());
+			}
+
+			Collection<Match> joinedValues = map.get(key);
+
+			for (String leftValue : leftValues) {
+				if (rightValues != null) {
+					for (String rightValue : rightValues) {
+						joinedValues.add(new Match(leftValue, rightValue));
+					}
+				} else {
+					joinedValues.add(new Match(leftValue, null));
+				}
+			}
+		}
+
+		if (outerJoinType == OuterJoinType.RIGHT || outerJoinType == OuterJoinType.FULL) {
+			for (Integer key : rightMap.keySet()) {
+				Collection<String> leftValues = leftMap.get(key);
+				Collection<String> rightValues = rightMap.get(key);
+
+				if (leftValues != null) {
+					continue;
+				}
+
+				if (!map.containsKey(key)) {
+					map.put(key, new ArrayList<Match>());
+				}
+
+				Collection<Match> joinedValues = map.get(key);
+
+				for (String rightValue : rightValues) {
+					joinedValues.add(new Match(null, rightValue));
+				}
+			}
+		}
+
+		return map;
+	}
+
+
+	private Map<Integer, Collection<String>> collectData(MutableObjectIterator<Tuple2<Integer, String>> iter)
+			throws Exception {
+		final Map<Integer, Collection<String>> map = new HashMap<Integer, Collection<String>>();
+		Tuple2<Integer, String> pair = new Tuple2<Integer, String>();
+
+		while ((pair = iter.next(pair)) != null) {
+			final Integer key = pair.getField(0);
+
+			if (!map.containsKey(key)) {
+				map.put(key, new ArrayList<String>());
+			}
+
+			Collection<String> values = map.get(key);
+			final String value = pair.getField(1);
+			values.add(value);
+		}
+
+		return map;
+	}
+
+}

http://git-wip-us.apache.org/repos/asf/flink/blob/941ac6df/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/NonReusingSortMergeInnerJoinIteratorITCase.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/NonReusingSortMergeInnerJoinIteratorITCase.java b/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/NonReusingSortMergeInnerJoinIteratorITCase.java
index 7fc3734..6548052 100644
--- a/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/NonReusingSortMergeInnerJoinIteratorITCase.java
+++ b/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/NonReusingSortMergeInnerJoinIteratorITCase.java
@@ -135,7 +135,7 @@ public class NonReusingSortMergeInnerJoinIteratorITCase {
 					collectData(input2));
 
 			final FlatJoinFunction<Tuple2<Integer, String>, Tuple2<Integer, String>, Tuple2<Integer, String>> joinFunction =
-					new MatchRemovingMatcher(expectedMatchesMap);
+					new MatchRemovingJoiner(expectedMatchesMap);
 
 			final Collector<Tuple2<Integer, String>> collector = new DiscardingOutputCollector<Tuple2<Integer, String>>();
 	
@@ -226,7 +226,7 @@ public class NonReusingSortMergeInnerJoinIteratorITCase {
 			input1 = new MergeIterator<Tuple2<Integer, String>>(inList1, comparator1.duplicate());
 			input2 = new MergeIterator<Tuple2<Integer, String>>(inList2, comparator2.duplicate());
 			
-			final FlatJoinFunction<Tuple2<Integer, String>, Tuple2<Integer, String>, Tuple2<Integer, String>> joinFunction = new MatchRemovingMatcher(expectedMatchesMap);
+			final FlatJoinFunction<Tuple2<Integer, String>, Tuple2<Integer, String>, Tuple2<Integer, String>> joinFunction = new MatchRemovingJoiner(expectedMatchesMap);
 			
 			final Collector<Tuple2<Integer, String>> collector = new DiscardingOutputCollector<Tuple2<Integer, String>>();
 	

http://git-wip-us.apache.org/repos/asf/flink/blob/941ac6df/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/NonReusingSortMergeOuterJoinIteratorITCase.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/NonReusingSortMergeOuterJoinIteratorITCase.java b/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/NonReusingSortMergeOuterJoinIteratorITCase.java
new file mode 100644
index 0000000..1205bc1
--- /dev/null
+++ b/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/NonReusingSortMergeOuterJoinIteratorITCase.java
@@ -0,0 +1,82 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.flink.runtime.operators.sort;
+
+import org.apache.flink.api.common.typeutils.TypeComparator;
+import org.apache.flink.api.common.typeutils.TypePairComparator;
+import org.apache.flink.api.common.typeutils.TypeSerializer;
+import org.apache.flink.runtime.io.disk.iomanager.IOManager;
+import org.apache.flink.runtime.jobgraph.tasks.AbstractInvokable;
+import org.apache.flink.runtime.memorymanager.MemoryManager;
+import org.apache.flink.runtime.operators.sort.AbstractMergeOuterJoinIterator.OuterJoinType;
+import org.apache.flink.util.MutableObjectIterator;
+import org.junit.Test;
+
+public class NonReusingSortMergeOuterJoinIteratorITCase  extends AbstractSortMergeOuterJoinIteratorITCase {
+
+	@Override
+	protected <T1, T2> AbstractMergeOuterJoinIterator createOuterJoinIterator(OuterJoinType outerJoinType, MutableObjectIterator<T1> input1,
+																			  MutableObjectIterator<T2> input2, TypeSerializer<T1> serializer1,
+																			  TypeComparator<T1> comparator1, TypeSerializer<T2> serializer2, TypeComparator<T2> comparator2,
+																			  TypePairComparator<T1, T2> pairComparator, MemoryManager memoryManager, IOManager ioManager,
+																			  int numMemoryPages, AbstractInvokable parentTask) throws Exception {
+		return new NonReusingMergeOuterJoinIterator(outerJoinType, input1, input2, serializer1, comparator1,
+				serializer2, comparator2, pairComparator, memoryManager, ioManager, numMemoryPages, parentTask);
+	}
+
+	@Test
+	public void testFullOuterWithSample() throws Exception {
+		super.testFullOuterWithSample();
+	}
+
+	@Test
+	public void testLeftOuterWithSample() throws Exception {
+		super.testLeftOuterWithSample();
+	}
+
+	@Test
+	public void testRightOuterWithSample() throws Exception {
+		super.testRightOuterWithSample();
+	}
+
+	@Test
+	public void testRightSideEmpty() throws Exception {
+		super.testRightSideEmpty();
+	}
+
+	@Test
+	public void testLeftSideEmpty() throws Exception {
+		super.testLeftSideEmpty();
+	}
+
+	@Test
+	public void testFullOuterJoinWithHighNumberOfCommonKeys() {
+		testOuterJoinWithHighNumberOfCommonKeys(OuterJoinType.FULL, 200, 500, 2048, 0.02f, 200, 500, 2048, 0.02f);
+	}
+
+	@Test
+	public void testLeftOuterJoinWithHighNumberOfCommonKeys() {
+		testOuterJoinWithHighNumberOfCommonKeys(OuterJoinType.LEFT, 200, 10, 4096, 0.02f, 100, 4000, 2048, 0.02f);
+	}
+
+	@Test
+	public void testRightOuterJoinWithHighNumberOfCommonKeys() {
+		testOuterJoinWithHighNumberOfCommonKeys(OuterJoinType.RIGHT, 100, 10, 2048, 0.02f, 200, 4000, 4096, 0.02f);
+	}
+}

http://git-wip-us.apache.org/repos/asf/flink/blob/941ac6df/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/ReusingSortMergeInnerJoinIteratorITCase.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/ReusingSortMergeInnerJoinIteratorITCase.java b/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/ReusingSortMergeInnerJoinIteratorITCase.java
index e4eec86..39316e3 100644
--- a/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/ReusingSortMergeInnerJoinIteratorITCase.java
+++ b/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/ReusingSortMergeInnerJoinIteratorITCase.java
@@ -135,7 +135,7 @@ public class ReusingSortMergeInnerJoinIteratorITCase {
 				collectData(input2));
 
 			final FlatJoinFunction<Tuple2<Integer, String>, Tuple2<Integer, String>, Tuple2<Integer, String>> joinFunction =
-					new MatchRemovingMatcher(expectedMatchesMap);
+					new MatchRemovingJoiner(expectedMatchesMap);
 
 			final Collector<Tuple2<Integer, String>> collector = new DiscardingOutputCollector<Tuple2<Integer, String>>();
 
@@ -226,7 +226,7 @@ public class ReusingSortMergeInnerJoinIteratorITCase {
 			input1 = new MergeIterator<Tuple2<Integer, String>>(inList1, comparator1.duplicate());
 			input2 = new MergeIterator<Tuple2<Integer, String>>(inList2, comparator2.duplicate());
 			
-			final FlatJoinFunction<Tuple2<Integer, String>, Tuple2<Integer, String>, Tuple2<Integer, String>> matcher = new MatchRemovingMatcher(expectedMatchesMap);
+			final FlatJoinFunction<Tuple2<Integer, String>, Tuple2<Integer, String>, Tuple2<Integer, String>> matcher = new MatchRemovingJoiner(expectedMatchesMap);
 			
 			final Collector<Tuple2<Integer, String>> collector = new DiscardingOutputCollector<Tuple2<Integer, String>>();
 	

http://git-wip-us.apache.org/repos/asf/flink/blob/941ac6df/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/ReusingSortMergeOuterJoinIteratorITCase.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/ReusingSortMergeOuterJoinIteratorITCase.java b/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/ReusingSortMergeOuterJoinIteratorITCase.java
new file mode 100644
index 0000000..b4fbd80
--- /dev/null
+++ b/flink-runtime/src/test/java/org/apache/flink/runtime/operators/sort/ReusingSortMergeOuterJoinIteratorITCase.java
@@ -0,0 +1,82 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.flink.runtime.operators.sort;
+
+import org.apache.flink.api.common.typeutils.TypeComparator;
+import org.apache.flink.api.common.typeutils.TypePairComparator;
+import org.apache.flink.api.common.typeutils.TypeSerializer;
+import org.apache.flink.runtime.io.disk.iomanager.IOManager;
+import org.apache.flink.runtime.jobgraph.tasks.AbstractInvokable;
+import org.apache.flink.runtime.memorymanager.MemoryManager;
+import org.apache.flink.runtime.operators.sort.AbstractMergeOuterJoinIterator.OuterJoinType;
+import org.apache.flink.util.MutableObjectIterator;
+import org.junit.Test;
+
+public class ReusingSortMergeOuterJoinIteratorITCase extends AbstractSortMergeOuterJoinIteratorITCase {
+
+	@Override
+	protected <T1, T2> AbstractMergeOuterJoinIterator createOuterJoinIterator(OuterJoinType outerJoinType, MutableObjectIterator<T1> input1,
+																			  MutableObjectIterator<T2> input2, TypeSerializer<T1> serializer1,
+																			  TypeComparator<T1> comparator1, TypeSerializer<T2> serializer2, TypeComparator<T2> comparator2,
+																			  TypePairComparator<T1, T2> pairComparator, MemoryManager memoryManager, IOManager ioManager,
+																			  int numMemoryPages, AbstractInvokable parentTask) throws Exception {
+		return new ReusingMergeOuterJoinIterator(outerJoinType, input1, input2, serializer1, comparator1,
+				serializer2, comparator2, pairComparator, memoryManager, ioManager, numMemoryPages, parentTask);
+	}
+
+	@Test
+	public void testFullOuterWithSample() throws Exception {
+		super.testFullOuterWithSample();
+	}
+
+	@Test
+	public void testLeftOuterWithSample() throws Exception {
+		super.testLeftOuterWithSample();
+	}
+
+	@Test
+	public void testRightOuterWithSample() throws Exception {
+		super.testRightOuterWithSample();
+	}
+
+	@Test
+	public void testRightSideEmpty() throws Exception {
+		super.testRightSideEmpty();
+	}
+
+	@Test
+	public void testLeftSideEmpty() throws Exception {
+		super.testLeftSideEmpty();
+	}
+
+	@Test
+	public void testFullOuterJoinWithHighNumberOfCommonKeys() {
+		testOuterJoinWithHighNumberOfCommonKeys(OuterJoinType.FULL, 200, 500, 2048, 0.02f, 200, 500, 2048, 0.02f);
+	}
+
+	@Test
+	public void testLeftOuterJoinWithHighNumberOfCommonKeys() {
+		testOuterJoinWithHighNumberOfCommonKeys(OuterJoinType.LEFT, 200, 10, 4096, 0.02f, 100, 4000, 2048, 0.02f);
+	}
+
+	@Test
+	public void testRightOuterJoinWithHighNumberOfCommonKeys() {
+		testOuterJoinWithHighNumberOfCommonKeys(OuterJoinType.RIGHT, 100, 10, 2048, 0.02f, 200, 4000, 4096, 0.02f);
+	}
+}

http://git-wip-us.apache.org/repos/asf/flink/blob/941ac6df/flink-runtime/src/test/java/org/apache/flink/runtime/operators/testutils/Match.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/test/java/org/apache/flink/runtime/operators/testutils/Match.java b/flink-runtime/src/test/java/org/apache/flink/runtime/operators/testutils/Match.java
index 539d864..4ac9093 100644
--- a/flink-runtime/src/test/java/org/apache/flink/runtime/operators/testutils/Match.java
+++ b/flink-runtime/src/test/java/org/apache/flink/runtime/operators/testutils/Match.java
@@ -21,7 +21,7 @@ package org.apache.flink.runtime.operators.testutils;
 /**
  * Utility class for keeping track of matches in join operator tests.
  *
- * @see org.apache.flink.runtime.operators.testutils.MatchRemovingMatcher
+ * @see MatchRemovingJoiner
  */
 public class Match {
 	private final String left;

http://git-wip-us.apache.org/repos/asf/flink/blob/941ac6df/flink-runtime/src/test/java/org/apache/flink/runtime/operators/testutils/MatchRemovingJoiner.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/test/java/org/apache/flink/runtime/operators/testutils/MatchRemovingJoiner.java b/flink-runtime/src/test/java/org/apache/flink/runtime/operators/testutils/MatchRemovingJoiner.java
new file mode 100644
index 0000000..e588d92
--- /dev/null
+++ b/flink-runtime/src/test/java/org/apache/flink/runtime/operators/testutils/MatchRemovingJoiner.java
@@ -0,0 +1,58 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.flink.runtime.operators.testutils;
+
+import org.apache.flink.api.common.functions.FlatJoinFunction;
+import org.apache.flink.api.java.tuple.Tuple2;
+import org.apache.flink.util.Collector;
+import org.junit.Assert;
+
+import java.util.Collection;
+import java.util.Map;
+
+
+public final class MatchRemovingJoiner implements FlatJoinFunction<Tuple2<Integer,String>,Tuple2<Integer,String>,Tuple2<Integer,String>> {
+	private static final long serialVersionUID = 1L;
+
+	private final Map<Integer, Collection<Match>> toRemoveFrom;
+
+	public MatchRemovingJoiner(Map<Integer, Collection<Match>> map) {
+		this.toRemoveFrom = map;
+	}
+
+	@Override
+	public void join(Tuple2<Integer, String> rec1, Tuple2<Integer, String> rec2, Collector<Tuple2<Integer, String>> out) throws Exception {
+		final Integer key = rec1 != null ? (Integer) rec1.getField(0) : (Integer) rec2.getField(0);
+		final String value1 = rec1 != null ? (String) rec1.getField(1) : null;
+		final String value2 = rec2 != null ? (String) rec2.getField(1) : null;
+
+		Collection<Match> matches = this.toRemoveFrom.get(key);
+		if (matches == null) {
+			Assert.fail("Match " + key + " - " + value1 + ":" + value2 + " is unexpected.");
+		}
+
+		boolean contained = matches.remove(new Match(value1, value2));
+		if (!contained) {
+			Assert.fail("Produced match was not contained: " + key + " - " + value1 + ":" + value2);
+		}
+		if (matches.isEmpty()) {
+			this.toRemoveFrom.remove(key);
+		}
+	}
+}

http://git-wip-us.apache.org/repos/asf/flink/blob/941ac6df/flink-runtime/src/test/java/org/apache/flink/runtime/operators/testutils/MatchRemovingMatcher.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/test/java/org/apache/flink/runtime/operators/testutils/MatchRemovingMatcher.java b/flink-runtime/src/test/java/org/apache/flink/runtime/operators/testutils/MatchRemovingMatcher.java
deleted file mode 100644
index f69b4d7..0000000
--- a/flink-runtime/src/test/java/org/apache/flink/runtime/operators/testutils/MatchRemovingMatcher.java
+++ /dev/null
@@ -1,58 +0,0 @@
-/*
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License.  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.apache.flink.runtime.operators.testutils;
-
-import org.apache.flink.api.common.functions.FlatJoinFunction;
-import org.apache.flink.api.java.tuple.Tuple2;
-import org.apache.flink.util.Collector;
-import org.junit.Assert;
-
-import java.util.Collection;
-import java.util.Map;
-
-
-public final class MatchRemovingMatcher implements FlatJoinFunction<Tuple2<Integer,String>,Tuple2<Integer,String>,Tuple2<Integer,String>> {
-	private static final long serialVersionUID = 1L;
-
-	private final Map<Integer, Collection<Match>> toRemoveFrom;
-
-	public MatchRemovingMatcher(Map<Integer, Collection<Match>> map) {
-		this.toRemoveFrom = map;
-	}
-
-	@Override
-	public void join(Tuple2<Integer, String> rec1, Tuple2<Integer, String> rec2, Collector<Tuple2<Integer, String>> out) throws Exception {
-		final Integer key = rec1 != null ? (Integer) rec1.getField(0) : (Integer) rec2.getField(0);
-		final String value1 = rec1 != null ? (String) rec1.getField(1) : null;
-		final String value2 = rec2 != null ? (String) rec2.getField(1) : null;
-
-		Collection<Match> matches = this.toRemoveFrom.get(key);
-		if (matches == null) {
-			Assert.fail("Match " + key + " - " + value1 + ":" + value2 + " is unexpected.");
-		}
-
-		boolean contained = matches.remove(new Match(value1, value2));
-		if (!contained) {
-			Assert.fail("Produced match was not contained: " + key + " - " + value1 + ":" + value2);
-		}
-		if (matches.isEmpty()) {
-			this.toRemoveFrom.remove(key);
-		}
-	}
-}